Silent coronary heart disease in patients with type 2 diabetes: application of a screening approach in a follow-up study

Abstract

Aims: The cost-effectiveness of screening for silent coronary heart disease (CHD) in type 2 diabetes (DM2) is still debated.

Methods: We applied a diagnostic algorithm for silent CHD detection, in a cohort of 102 asymptomatic DM2 subjects (57±7years), attending 5 Italian outpatient clinics, to verify its predictive value. The risk of silent CHD was calculated considering classical risk factors, and presence of microangiopathy/macroangiopathy. Patients were divided in 3 groups, i.e. group 1: normal ECG and low silent CHD risk; group 2: abnormal ECG, irrespective of silent CHD risk; group 3: high silent CHD risk, irrespective of ECG. To group 2 and 3, a functional test was recommended and performed in 78% of patients.

Results: Silent CHD prevalence was similar in group 2 and 3 (25 vs. 17% respectively; p=0.495). However, evaluating the entire cohort, a significant higher prevalence of silent CHD was observed in subjects with abnormal vs. normal ECG (23 vs. 4%; P=0.004), but not in subjects with high vs. low pre-test silent CHD risk (14 vs. 9%; p=0.472).

Conclusions: An abnormal ECG was a strong, independent predictor of silent CHD (OR 8.9; CI 1.27-62.5; p=0.028) in DM2. Therefore, a functional stress testing should be considered in DM2 patients with ECG abnormalities.

Keywords: CHD diagnosis; Diabetes complications; Electrocardiogram; Positive predictive value; Silent coronary heart disease ischemia; Type 2 diabetes.